A typical longwall mining apparatus such as described in German patent documents 3,318,360 of P. Heintzmann, 3,514,439 of G. Blumenthal, 3,743,239 of G. Blumenthal (U.S. equivalent Pat. No. 4,883,322), and 4,004,488 of K. Plaga (U.S. equivalent Pat. No. 5,088,796) have a main conveyor chain that extends as parallel front and rear stretches along a face being worked between a pair of turnaround locations. One of the turnaround locations is in a takeoff shaft or heading leading back from the face and containing a takeoff conveyor and the other is in an access shaft or heading that normally extends parallel to the takeoff shaft. The rear stretch of the chain runs in a conveyor trough parallel to the face and the front stretch runs along the face being worked. Conveyor/cutting elements mounted on the chain are set in the front stretch in a vertical position in which they engage the face and plow material off it, and are moved in the rear stretch to a horizontal position in the trough where they push the recovered material along to the end of the trough where a takeoff conveyor extending away from the face in the takeoff shaft carries away the recovered material.
As a rule a main drive is provided in the main takeoff shaft where there is substantial room, and an auxiliary drive is provided at the other turnaround location in the small access shaft at the other end of the face being worked. A separate device at the takeoff-shaft turnaround location transfers the material from the conveyor trough to the takeoff conveyor.
Thus the known devices are fairly bulky and quite complex. This is true regardless of the length of the face or whether the device is being used to back-cut the face.